Hurlburt Field Air Force Base, Okaloosa County, Fla.
RETROFIT TEAM
- ROOFING INSTALLER: Royster Contracting LLC, Fort Walton Beach, Fla.
- GENERAL CONTRACTOR: CCI Mechanical LLC, Shalimar, Fla.
MATERIALS
The existing 7,800-square-foot metal building needed a new metal roof. In lieu of removing the existing metal roof and replacing it, the Base Facility Construction Department moved forward with a metal-over-metal retrofit in which a new metal roof is installed over new structural sub-framing that attaches directly to the existing roof’s support system without removing the existing metal roof. In addition, the retrofit roof system was engineered to withstand a Category 5 hurricane of 157-mph wind speed.
Approximately 2,700 lineal feet of standard Model “C” sub-framing, manufactured to fit over 12-inch on-center PBR rib panels, was installed on the existing roof. Then 3 inches of fiberglass insulation was applied before 24-inch-wide Central Seam Plus trapezoidal standing-seam panels—24 gauge in Brite White—completed the system.
SUB-FRAMING MANUFACTURER: Roof Hugger LLC
STANDING-SEAM ROOF MANUFACTURER: Central States Manufacturing Inc.
THE RETROFIT
Increasing wind-uplift resistance on metal-over-metal retrofit roofs in the coastal states is very common. Many older buildings engineered for a 90- to 100-mph wind speed must be upgraded to minimum code requirements of 120-mph inland and 130 mph for coastal areas. Some parts of Florida and Texas have requirements of 155 mph or greater. U.S. government facilities typically exceed locally adopted codes.
When Category 5 Hurricane Michael struck the Florida Panhandle in October 2018, it caused catastrophic damage at Tyndall Air Force Base, which only is 82 miles from Hurlburt Field Air Force Base. Even with Michael’s documented peak wind speed of 155 mph, Hurlburt’s metal-over-metal retrofit roof suffered no damage.
PHOTO: Roof Hugger LLC